The invention relates to an apparatus for forming and containing semi-solid samples of reproducible thickness for the performing of optical measurements thereon. In another aspect, the invention relates to a method for taking optical measurements of a semi-solid sample.
In colorimetric and spectrophotometric studies, sample containers are required for holding the samples to be studied. The sample containers provided by the prior art were not well adapted for the study of semi-solid samples which include, for example, gels, amorphous polymers, and highly viscous liquids. Semi-solid samples do not flow as readily as the liquids for which the cells provided by the prior art were designed. Because of this, it was difficult to force semi-solid samples to fit into the contours of prior art cells to obtain reproducible sample dimensions. It has thus been difficult to obtain samples of semi-solid materials having reproducible thickness by utilizing the sample cells of the prior art. Difficulties were also encountered in obtaining bubble-free samples, and also in cleaning the sample cells after use. For quantitative studies of the optical properties of semi-solid materials, it is thus extremely desirable to have an easy-to-clean apparatus for producing bubble-free semi-solid samples of reproducible thicknesses.